When it comes to reproductive rights, even liberals are likely to hesitate, to cite bioethics, or to say that abortion is a necessary evil. They're likely to say that it should be safe, legal and rare.
But here's the thing about abortion: the only way you could possibly have doubts as to whether everyone should have completely unfettered access to it is if you're either uncertain about bodily autonomy as a right everybody has, or if you're uncertain about whether it's something people other than cis men should have.
I don't think anyone is really uncertain about bodily autonomy. At least for cis men, we're generally in agreement that one of the rights that all human beings have is to not have any other person in their body without consent.
One of the times when we decide to suspend personhood is when somebody is imprisoned. The widespread acceptability of prison rape jokes shows that the one situation when we consider suspending bodily autonomy okay is when we think somebody deserves to be punished.
So there are really only two reasons for thinking abortion is a moral gray area:
- You don't think women are really people.
- You think women should be punished for having sex.
Of course, cis men don't get punished for having sex with other consenting adults, because having sex with other consenting adults is something that human adults get to do. So it comes down to whether or not you're sure women are really people.
(While the effect of forced pregnancy is that everyone with a uterus, including cis women and trans men like me, as well as genderqueer people who have uteruses, the intent behind the pro-forced-pregnancy movement is to control women and punish them for existing as sexual beings. We need to be aware of both effects and intent here.)
Are you sure that women are people? Then surely you believe that nobody has a right to be in a woman's body without her consent.
Do you think that having sex grants implicit consent to pregnancy? Then you don't really think women are people, because we're all fine with men having consensual sex and don't, as a rule, believe they waive any of their basic human rights by doing so. Thinking women waive their bodily autonomy by choosing to have sex really just amounts to treating pregnancy as a punishment for sex.
I'm assuming that people who have doubts about abortion believe that fetuses and embryos are people. If they don't think that, then I really don't know what they're on about (although there is plenty of evidence they don't really think that -- ask a pro-forced-pregnancy person whether they favor punishing somebody who has an abortion in the same way that people who commit murder are punished.) Believing that fetuses are people poses no threat to my believe in the fundamental right to an abortion. Like all people, fetuses have no right to be in any other person's body without that person's consent.[*]
And yet, in 2016, I still live in a country where people considered liberal, progressive, in favor of civil liberties, and so on can still say abortion is a moral gray area with a straight face. I still live in a country where even liberals, even people who support personal freedom, haven't made up their mind about whether women are people.
[*] In answer to the question, raised elsewhere, of what we say if we believe fetuses are people and recognize that they didn't consent to be in the body of their gestational parent: I'd say three things to that. First, the concept that you have the right to self-defense isn't too controversial. You can come up with plenty of reasons why an adult person who is posing a threat to you might not be a totally free agent, but ultimately, your right to defend your body against invasion by them is considered sacrosanct. Second, fetuses don't have the ability to defend themselves, and I'm happy to defer that particular what-if to the time when that changes. And third, being in a situation you didn't consent to doesn't generally confer the right to use somebody else's body -- for example, if you would die without a kidney transplant, and if you didn't consent to have kidney failure, that still doesn't give you the right to force someone to donate their kidney to you if they don't want to.